1. Field of the Invention
The invention concerns calipers, especially calipers designed for surgical use.
2. Description of Related Art
In order to obtain access to certain lesions lying on the opposite side of a bone structure, relatively large holes (up to 20 mm diameter) must be drilled during a surgical procedure. In order to replace the removed bone either with an appliance or a bone plug, it is desirable to determine the exact depth and diameter of the drilled hole. Calipers or depth gauges currently available for making such measurements require two hands for use, one to hold the instrument in position and the other to release and lock a movable element. Some such instruments provide a direct reading of the measurement, while others require the measured span to be laid against a scale. When the drilled hole is to be filled with a bone plug, it must also be measured.